U4254BM-MFPG3 Atmel, U4254BM-MFPG3 Datasheet
U4254BM-MFPG3
Specifications of U4254BM-MFPG3
Related parts for U4254BM-MFPG3
U4254BM-MFPG3 Summary of contents
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... Low-power Consumption Electrostatic sensitive device. Observe precautions for handling. Description The U4254BM integrated low-noise AM/FM antenna impedance matching cir- cuit in BiCMOS technology. The device is designed specifically for car applications and is suitable for windshield and roof antennas. Figure 1. Block Diagram 1 (14) ...
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... Pin Description Pin SSO16 Pin QFN16 U4254BM-M 2 Figure 3. Pinning QFN16 FMOUT AGCADJ 13 VREF1 12 AMOUT1 11 AMOUT Symbol Function FMIN FM input GND1 Ground for FM part FMGAIN FM gain adjustment AGC AGC output VREF2 Reference voltage 2 output NC Not connected GND2 Ground for AM part AMIN AM input ...
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... This diode dampens the antenna’s input signal and protects the amplifier input against overload. The maximum current which flows in the AGC pin is approximately 1 mA. In low-end applications, the AGC function is not necessary and the external components can therefore be omitted. U4254BM-M ESD ESD 3 ...
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... AGCADJ FMOUT U4254BM-M 4 Figure 6. Internal Circuit at Pin AGC AGC The threshold of the AGC can be adjusted by varying the DC current at pin AGCADJ. If pin AGCADJ is connected directly to GND1, the threshold is set to 96 dBµV at the FM amplifier output resistor is connected between AGCADJ and GND1, the threshold is shifted to higher values with increasing resistances. If AGCADJ is open, the threshold is set to 106 dBµ ...
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... Figure 10. Internal Circuit at Pins AMOUT1 and AMOUT VREF1 is the stabilized voltage for the AM amplifier and the AGC block. To achieve excellent noise performance at LW frequencies recommended that this pin be con- nected to ground via an external capacitor of about 1 µF. U4254BM-M VREF1/2 470 k ESD AMOUT1 ...
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... VREF2 GND2 U4254BM-M 6 Figure 11. Internal Circuit at Pin VREF1 VS GND1 For the DC biasing of the FM amplifier, a second voltage reference circuit is integrated. Since the collector current is temperature independent, the output voltage has a nega- tive temperature coefficient of about -1 mV/K. To stabilize this voltage, an external capacitor to ground of a few nF is recommended. ...
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... Parameters Junction ambient 4772C–AUDR–08/04 The U4254BM integrated AM/FM antenna impedance matching circuit. It com- pensates cable losses between the antenna (for example windshield, roof or bumper antennas) and the car radio which is usually placed far away from the antenna. The FM amplifier provides excellent noise performance. External components are used to adjust the gain and the input-output matching impedance ...
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... Voltage gain Output noise voltage (rms value) 2nd harmonic FM Amplifier Supply current limit Input resistance Output resistance Power gain Output noise voltage 3rd-order output intercept AGC AGC input voltage threshold AGC input voltage threshold AGC output current U4254BM-M 8 Test Conditions Pin switched to 2 ...
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... Figure 13. Test Circuit FMOUT 150 FMIN 4772C–AUDR–08/ 2.2 µ 2.2 15 100 nF µF 2 2.2 nF 2.2 µH 2 2.2 nF U4254BM AMOUT 100 AMIN 9 ...
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... Figure 14. FM Intermodulation Distortion dBµV Input 103 dBµ Input dBµV 118 dBµ U4254BM-M 10 dBµV Gain = 5 dB AGC not active 100 105 MHz dBµV AGC active 100 105 MHz Output 108 dBµV 58 dBµ 100 105 Output 100 dBµV 50 dBµV ...
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... Figure 15. Test Circuit for AM Large Signal Behavior LPF f = 500 kHz cutoff 500 kHz V 0 4772C–AUDR–08/04 100 nF AMOUT1 DUT AMIN 1 nF AMOUT 100 nF 50 Figure 16. AM Harmonic Distortion V AMOUT (dBµV) 115 dBµV 110 0.5 U4254BM-M Analyzer dBµV 115 dBµV 55 dBµV 45 dBµV f (MHz) 1.0 1.5 11 ...
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... Figure 17. Application Circuit U4254BM-M 12 4772C–AUDR–08/04 ...
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... Package Information Package SO16 Dimensions 4772C–AUDR–08/04 Package SO16 SO16 QFN16 QFN16 10.0 9.85 0.4 1.27 8. U4254BM-M Remarks – Taping corresponding, ICE-286-3 – Taping corresponding, ICE-286-3 5.2 4.8 3.7 1.4 0.2 0.25 3.8 0.10 6.15 5.85 technical drawings according to DIN ...
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... U4254BM-M 14 4772C–AUDR–08/04 ...
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... No licenses to patents or other intellectual property of Atmel are granted by the Company in connection with the sale of Atmel products, expressly or by implication. Atmel’s products are not authorized for use as critical components in life support devices or systems. ...